YFZ Big Bore Kits

Big Bore kits are Just that. They are a bolt-on cylinder kit that uses your oem or exsiting crankshaft.

Sizes for the YFZ are;

2004-2007 450cc to 500cc

These Big Bore Kits are showing Huge HP gains Just bolting them on. These Kits include an aluminum Cast Cylinder (Nickel Silicon Carbide Coated Bore) Wiseco piston, wrist pin and piston rings. Gasket set Including base, head, cam tensioner gasket and Pipe gasket. We can install this cylinder for you and save you some work. Use our Professional Build team to check your motor and install this kit correctly. This Kit will work on all years regardless of your crank. We just need to know what year your bike is so we can match the correct stroke cylinder to your motor.



Available Options;

04-05 crank 98mm bore 470cc Call for pricing
04-05 crank 100mm bore 490cc Call for pricing
06 crank 98mm bore 480cc Call for pricing
06 crank 100mm bore 500cc Call for pricing



Kit includes NEW cast aluminum Cylinder, Piston Gaskets, Piston, Rings, Crankshaft. Many Options are available Piston Brand, Compression, crankshaft brand.


Stroker Kits are cylinder kits that require a stroked crankshaft. You must replace your OEM crankshaft or if you have a stroker crankshaft your cylinder must match your crankshaft.

YFZ Stroker Cylinder Kit options are;

2004-2007 500cc-565cc

These Big Bore STROKER Kits are showing Huge HP gains Just bolting them on. These Kits include an aluminum Cast Cylinder (Nickel Silicon Carbide Coated Bore) Wiseco piston, wrist pin and piston rings. Gasket set Including base, head, cam tensioner gasket and Pipe gasket. We can install this cylinder for you and save you some work. Use our Professional Build team to check your motor and install this kit correctly. This Kit will work on all years regardless of your crank. We just need to know what year your bike is so we can match the correct stroke cylinder to your motor.





Available Options;

4mm stroker crank 498cc* Please call for pricing

4mm stroker crank 520cc* Please call for pricing

6mm stroker crank 513cc* Please call for pricing

6mm stroker crank 535cc* Please call for pricing

* requires a stroker crankshaft





Kit includes NEW cast aluminum Cylinder, Piston Gaskets, Piston, Rings, Crankshaft. Many Options are available Piston Brand, Compression, crankshaft brand.